This invention relates to electromagnetic interference caused by an electronic system. More particularly, this invention relates to an apparatus for reducing such electromagnetic interference.
Electronic systems are known to generate electromagnetic energy. Such energy generation can, in some instances, cause EMI (Electromagnetic Interference) if in proximity to other electronic systems. It is, therefore, desirable to reduce the amount of electromagnetic interference attributable to such systems.
Electromagnetic energy tends to leak from the interior of electronic systems through gaps defined between adjacent components of such systems. For example, when the outer sheet enclosure or chassis of an electronic system separates from adjacent inner modules such as card holders, electromagnetic leakage may occur. Generally, such separation can form gaps between the chassis and the inner modules. These gaps may result from manufacturing tolerances or deformation of the chassis due to the weight of units stacked in or near it.
Typically, EMI leakage causes transmission problems. Furthermore, electronic systems are required to comply with specific EMS emissions regulations.
Currently, additional fasteners (e.g., screws, clips, rivets, etc.) are installed to secure the chassis to the inner modules in the areas where gaps typically occur. However, such fasteners may be difficult to access if removal of one of the inner modules is required. Furthermore, fasteners may be dropped into the system during removal and cause damage to the system if they come into contact with current-carrying components.
Alternatively, spring fingers or gasket material may be installed to fill the areas where there are gaps. However, this is not always possible due to tight gap clearances. Also, spring finger and gasket materials may relax over time and become less effective.
Finally, these existing solutions (fasteners and filler material, for example) described heretofore may be difficult to apply to operating electronic systems in the field that develop EMI leakage problems.
Accordingly, there remains a need for reducing or eliminating gaps between adjacent components of an electronic system, thereby reducing electromagnetic interference generated by the electronic system.
According to one aspect of this invention, an apparatus is provided for reducing or eliminating a gap defined between adjacent components of an electronic system, thereby reducing electromagnetic interference generated by the electronic system. The apparatus includes a cam having a cam surface positionable adjacent a component of the electronic system. The cam is moveable to an actuated position in which the cam surface applies a force to the component. The apparatus further includes a support mountable to the electronic system. The support engages the cam and facilitates the movement of the cam. The movement of the cam with respect to the support and into the actuated position causes the cam surface to apply the force to the component, thereby reducing or eliminating a gap between the component and an adjacent component of the electronic system.
According to another aspect of this invention, an electronic system is provided to reduce electromagnetic interference generated thereby. The electronic system includes adjacent housing components and a frame supporting the housing components. The electronic system further includes a cam having a cam surface positionable adjacent one of the housing components. The cam is moveable to an actuated position in which the cam surface applies a force to the housing component. A support is mounted to the frame. The support engages the cam and facilitates the movement of the cam. The movement of the cam with respect to the support and into the actuated position causes the cam surface to apply the force to the housing component, thereby reducing or eliminating the gap between the adjacent components.
According to yet another aspect of this invention, a method is provided for reducing electromagnetic interference generated by an electronic system having adjacent components having a gap therebetween. The method includes the steps of moving a cam surface to apply a force to one of the adjacent components of the electronic system, and reducing the gap between the adjacent components by virtue of the force applied by the cam surface.